1. Field of the Invention
The present invention relates to a mounting board composed of a PC (printed circuit) board on which a flat-type electrical element is mounted, and a lead-attached electrical element that is flat in shape and has a lead bonded to each electrode face. The present invention relates particularly to technology for an improved structure for mounting the electrical element to the PC board, taking into account reductions in size.
2. Description of the Related Art
Conventionally, mounting boards including a microcomputer, memory, etc. often have a flat-type electrical element such as a battery or capacitor mounted thereon as a backup power supply. The term “flat-type electrical element” includes so-called “coin-type” and “button-type” electrical elements. Generally, one end of a lead is connected to the cathode face of the electrical element, and one end of another lead is connected to the anode face. The other end of each lead is soldered to the PC board, thereby mounting the electrical element to the PC board.
In recent years, there has been demand for reduced-size electrical equipment, which has lead to demand for reduced-size mounting boards. One strategy for meeting this demand includes various methods of mounting an electrical element to a mounting board so as to reduce the area occupied by the electrical element (occupied area) on the main face of the mounting board when viewed from above in a direction perpendicular to the main face of the mounting board.
For example, there is technology for soldering one main face (one electrode) of a flat-type battery directly to a conductive land on a PC board, thereby reducing the number of leads that are required and reducing the area occupied by the flat-type battery on the PC board (see Japanese Patent Application Publication No. 2002-298804).
After mounting an electrical element to a PC board in the above manner, in general the condition of the mounted electrical element is tested. If any sort of defect is found in the mounted electrical element, the electrical element must be detached from the mounting board. Specifically, an operator detaches each defective element separately by hand, by bringing a soldering iron into contact with the electrical element or lead that is soldered to the PC board in order to melt the solder. A new electrical element must then be re-soldered to a predetermined position on the PC board. This process is called rework.